Autologous hematopoietic stem cell transplant in pediatric solid tumours in India: A single centre experience of 15 years

Abstract

Background and Aim - High-dose chemotherapy followed by autologous hematopoietic stem cell transplant(ASCT) remains a curative option for many pediatric solid tumours when standard-dose chemotherapy fails. The Indian data regarding the use of ASCT in the treatment of pediatric solid tumours is scarce and limited to neuroblastoma. Method - In this study we report the outcomes of solid tumors in children, adolescents and young- adults (CAYA) who underwent ASCT in a tertiary centre of India. It includes patients from January 2008- August 2024. Results - Out of 84 patients with solid tumours in the CAYA age group transplanted, the median age was 6y (2-24), with 70.7% males. The diagnoses of the patients were neuroblastoma (NB=52%), relapsed/refractory germ-cell tumours (GCT=15.5%), relapsed/refractory ewing sarcoma (EWS=22.6%), retinoblastoma(RB) and soft-tissue sarcoma(STS) 4.7% each. While 41(48.8%) patients underwent ASCT during relapse, rest 43(51.2%) patients underwent upfront ASCT(NB). The conditioning regimens were: busulfan-melphalan or carboplatin-etoposide-melphalan for NB, melphalan or busulfan-melphalan for EWS, carboplatin-etoposide for GCT and thiotepa-carboplatin for STS/RB. Median stem-cell dose was 4.6 (1.8-20.1) million/kg, given after a median 13.5 days (4-110) days of cryopreservation. Toxicity details are given in Table 1. The median time to neutrophil engraftment was 11 days(9-25). With a median follow-up of 441 days, the estimated 1-year overall survival (OS) and event-free survival (EFS) for the entire cohort was 77.0% and 58.4%, respectively, better in GCT than NB or EWS. Conclusions - The evidence in support of ASCT in many pediatric solid tumours like relapsed-refractory GCT, high-risk/relapsed-refractory EWS, rhabdoid tumours and embryonal brain tumours is gradually increasing. Safe administration of this procedure in LMICs would improve.